1. Field of the Invention
The present invention relates generally to measurements of material properties, and particularly to an optical frequency-based method for measuring the complex dielectric constant of a substance.
2. Description of the Related Art
The measurement of the complex dielectric constant and complex permeability is required not only for scientific but also for industrial applications. For example, areas in which knowledge of the properties of materials at microwave frequencies is required include microwave heating, biological effects of microwaves, and nondestructive testing.
Although it is known to make measurements of the complex dielectric constant and complex permeability in the time domain, the calculations involved are complex and are dependent upon time and energy intensive Fourier transformations due to the measured transient response. Further, this technique typically only works within a severely limited band of frequencies, dependent upon the time response of the initial pulse and its repetition frequency. It would be desirable to be able to measure the complex dielectric constant directly in the frequency domain, allowing for measurements to be made over a wide range of frequencies, with calculations being relatively fast and simple.
Thus, a method for measuring the complex dielectric constant of a substance addressing the aforementioned problems is desired.